JP2008234871A - High-pressure discharge lamp and lighting fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp and a lighting fixture using the same capable of having low fading-out voltage by improvement of a halogen getter and showing high light-emitting efficiency from the beginning of lighting and maintaining the high light-emitting efficiency for a long period. <P>SOLUTION: The high-pressure discharge lamp comprises a translucent ceramic airtight container 1, a pair of electrodes 2, 2 sealed in the inside of the translucent ceramic airtight container, and a sealed-in object consisting of starting gas, metal halide including at least thulium (Tm), sodium (Na), and (thallium) Tl, mercury, and metal thulium and satisfying a numerical formula: 0.03≤A/B≤0.16 as a molar ratio A/B, provided the number of mols of metal thulium is A (mols) and the number of mols of the whole metal halide to be sealed in is B (mols). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-pressure discharge lamp in which a metal halide is enclosed in a translucent ceramic hermetic container and a lighting fixture using the same.

  In high-pressure discharge lamps such as metal halide lamps that encapsulate luminescent metal halides, the luminescent metal reacts with the tube wall material, etc. of the arc tube, or is electrophoresed and absorbed into the tube wall. It is known that free halogen is generated in the arc tube, and the lamp voltage and extinction voltage increase. In order to suppress this, it is known to enclose a halogen getter made of metal in an arc tube (see, for example, Patent Documents 1 to 3).

  In Patent Document 1, at least one metal halide of indium, thallium, and gallium is enclosed, and a rare earth metal is excessively enclosed as a halogen getter with respect to the halogen, and 88 lm / W is obtained in the example. . The arc tube is made of quartz glass.

  In Patent Document 2, scandium and sodium iodide are encapsulated, and metal scandium is encapsulated as a halogen getter. In addition, there is no description about luminous efficiency. The arc tube is made of alumina.

  In Patent Document 3, dysprosium, thulium and holmium halides are enclosed, and metal holmium is enclosed as a halogen getter. In addition, there is no description about luminous efficiency. The arc tube is made of alumina.

Japanese Patent Application Laid-Open No. 07-272677 JP 09-115480 A JP 09-270246 A

  In the above prior art, it is possible to capture the free halogen by enclosing the halogen getter to suppress the rise of the lamp voltage and the extinction voltage, but to show high luminous efficiency from the beginning of lighting and to maintain it for a long period of time. Is not necessarily effective.

  In addition, in the case of a high-pressure discharge lamp with a built-in starter equipped with a translucent ceramic hermetic container, the lamp efficiency and color rendering can be improved by increasing the operating temperature of the arc tube, but generally the starting voltage is high. Therefore, the increase in free halogen makes it easy for the arc to disappear during the lifetime, resulting in a problem that the lamp life is shortened.

  An object of the present invention is to provide a high-pressure discharge lamp that has a low extinction voltage due to the improvement of the halogen getter, exhibits high luminous efficiency from the beginning of lighting, and maintains it for a long period of time, and a lighting fixture using the same. To do.

  The high-pressure discharge lamp of the present invention includes a translucent ceramic hermetic container; a pair of electrodes sealed inside the translucent ceramic hermetic container; a starting gas sealed in the translucent ceramic hermetic container, at least thulium ( Tm), metal halides including sodium (Na) and thallium (Tl), mercury and metal thulium. The number of moles of metal thulium is A (mol) and the number of moles of all metal halides is B (mol). And the inclusion in which the molar ratio A / B satisfies the mathematical formula: 0.03 ≦ A / B ≦ 0.16.

  The present invention allows the following aspects.

  In the present invention, the following modes are allowed.

  [Translucent Ceramic Discharge Container] The translucent ceramic discharge container is composed of a single crystal metal oxide such as sapphire and a polycrystalline metal oxide such as translucent airtight aluminum oxide, yttrium-aluminum garnet. This is a discharge vessel made of a material having optical transparency and heat resistance such as (YAG), yttrium oxide (YOX), and polycrystalline non-oxide, for example, aluminum nitride (AlN). Note that the translucency means that the visible light generated by the discharge can be transmitted to the outside and transmitted to the outside, and is preferably transparent, but if necessary, it is light diffusive. Also good. And at least the surrounding part should just have translucency, and if necessary, a small diameter cylinder part may be light-shielding.

  Moreover, the translucent ceramics discharge container is provided with the surrounding part which surrounds discharge space. Moreover, the single or a pair of small diameter cylinder part arrange | positioned by communicating with the edge part of the surrounding part can be provided. When forming the small-diameter cylindrical portion, it is preferable that the surrounding portion and the small-diameter cylindrical portion are integrated by integral molding because the temperature distribution tends to be uniform and optical homogeneity is easily obtained. If the thermal or optical inhomogeneous structure of the material cross section is not particularly problematic, a shrink-fit structure may be used.

  The surrounding portion is a portion that surrounds the discharge in the inside thereof to define a discharge space, and the inner surface thereof is allowed to be formed into a continuous curved surface. Furthermore, the main part inside the surrounding portion can be formed into a bowl shape, an elliptical sphere, or a spherical hollow. The “main part” of the surrounding part refers to a part of the remainder excluding the vicinity of the end part on the side in contact with the small-diameter cylindrical part, and a part through which light emission by discharge is mainly transmitted.

  Next, when forming a small-diameter cylindrical portion, an electrode, which will be described later, and an introduction conductor connected to the electrode are inserted into the small-diameter cylindrical portion, and a slight gap called a capillary is formed around the electrode. The coldest part can be formed. Moreover, it can contribute to sealing a translucent ceramics discharge container to a small diameter cylinder part. In addition, the cross section of the small diameter cylindrical portion is preferably substantially circular.

  Further, it is preferable that the temperature of the outer surface of the surrounding portion during lighting of the translucent ceramic discharge vessel is 850 to 1200 ° C., and the temperature of the outer surface of the small diameter cylindrical portion is 600 to 900 ° C.

  [About a pair of electrodes] A pair of electrodes are arranged in the encircling part of a translucent ceramics discharge container so that the tip may be opposed across the discharge space. As a preferred configuration, the electrode is inserted into the small-diameter cylindrical portion while forming a slight gap with the inner surface of the small-diameter cylindrical portion, and the tip faces the surrounding portion of the translucent discharge vessel. An appropriate interelectrode distance is formed between the tips.

  In addition, the electrode can be formed using a conductive and refractory material such as tungsten (W), doped tungsten, molybdenum (Mo), cermet, or the like alone or in appropriate combination. Further, the electrode can be constituted of an elongated electrode shaft portion and an electrode main portion disposed at the tip portion of the electrode shaft portion. In this case, the electrode main portion is a portion that is disposed at the tip of the electrode shaft and mainly functions as a cathode and / or an anode, and constitutes the tip of the electrode. Moreover, the electrode main part can be wound with a tungsten coil as necessary in order to increase its surface area and improve heat dissipation.

  Furthermore, as described above, the tip of the electrode is in a position facing the inside of the surrounding part. However, facing the inside of the surrounding part means that the electrode is in the surrounding part and a small-diameter cylinder communicating with the inside of the surrounding part. It is a concept including the aspect located in a part. In addition, it is desirable that the intermediate portion of the electrode has a constant thickness in order to form a slight gap, that is, a capillary as uniform as possible between the inner surface of the small-diameter cylindrical portion of the translucent discharge vessel. Furthermore, it is allowed to wind a coil of pure tungsten (W), molybdenum (Mo), rhenium (Re), tungsten-rhenium alloy or doped tungsten around the middle part of the electrode. This facilitates centering of the electrode with respect to the small diameter cylindrical portion. The base end portion of the electrode is fixed at a required relative position with respect to the translucent discharge vessel, and is fixed by welding or the like to the tip of a current introduction conductor that functions to introduce current from the outside. Supported electrically and mechanically. For the purpose of thermally buffering during welding, a member such as molybdenum or cermet can be disposed at the distal end portion of the current introduction conductor, and the member can be interposed between the base end of the electrode. .

  Furthermore, the current introduction conductor can be constituted by a rod-shaped body of a sealing metal such as niobium, a pipe-shaped body or a coil-shaped body. In this case, since the sealing metal such as niobium is highly oxidizable, when the high pressure discharge lamp is lit in the atmosphere, the oxidation-resistant conductor is further connected to the introduction conductor, and the introduction conductor It is necessary to coat with a seal or the like so that the highly oxidizing sealing metal portion does not come into contact with the atmosphere.

  [About Inclusion] The inclusion is a characteristic component of the present invention. It contains a starting gas, at least a predetermined metal halide, mercury and metal thulium. That is, the encapsulant is a discharge medium and a halogen getter. The discharge medium is a predetermined metal halide, starting gas and mercury. In the present invention, the halogen getter is metal thulium. That is, when metal thulium captures free halogen to form thulium halide, thulium ions generated therefrom by ionization contribute to highly efficient light emission.

  The halide of the predetermined metal is a metal halide mainly contributing to light emission, and includes at least thulium (Tm), sodium (Na), and thallium (Tl) metal halides. The metal ions generated by the metal halide share the main part of light emission of the high-pressure discharge lamp. Therefore, the metal halide functions as a main component of a so-called metal halide. In particular, thulium ions generated by thulium halide function as an important light-emitting element particularly for high-efficiency light emission. In the present invention, it is preferable that the mole% ratio of thulium halide is in the range of 20 to 30 (mol%) with respect to all the metal halides to be encapsulated. The reason will be described with reference to FIG.

  FIG. 1 is a graph showing the relationship between the extinction rate during the lifetime and the lamp efficiency with respect to the molar ratio of thulium halide / metal halide. In the figure, the horizontal axis represents thulium halide / metal halide (mol% ratio), the vertical axis represents the occurrence rate of extinction (%) during the lifetime, and the right side represents lamp efficiency (lm / W). In addition, the curve with the measured value ♦ disappears and shows the voltage characteristic, and the curve with the measured value □ shows the lamp efficiency characteristic.

  As can be understood from the figure, if the thulium halide / metal halide (mol% ratio) is 30 (mol%) or less, the occurrence rate of extinction of the high-pressure discharge lamp is very small and acceptable. When the amount exceeds (mol%), the rate of disappearance suddenly increases and deviates from the allowable range. On the other hand, the lamp efficiency is high and acceptable when the thulium halide / metal halide (mol% ratio) is 20 (mol%) or more, but the lamp efficiency decreases when it is less than 20 (mol%). Deviate from the allowable range.

  In summary, if the thulium halide / metal halide (mol% ratio) is in the range of 20-30, it can be said that the rate of extinction of the high-pressure discharge lamp is extremely small and the lamp efficiency is high, which is preferable. .

  Further, a part of the thulium halide can be optionally substituted with at least one metal halide of cerium (Ce) and praseodymium (Pr). The range of permissible substitution is more than 10% by weight and less than 20% by weight for all metal halides. Further, the enclosed mass of thulium halide can be set to a ratio of more than 100% and less than 700% with respect to the enclosed amount of at least one halide of cerium (Ce) and praseodymium (Pr). It should be noted that cerium metal halide provides more favorable results than praseodymium. By doing so, it is possible to obtain a high-pressure discharge lamp having a lamp efficiency of 110 lm / W or more, an average color rendering index Ra80 or more, and a small chromaticity deviation.

  Further, at least one metal halide of indium (In) and manganese (Mn) can be added for chromaticity adjustment. In this case, the enclosed mass (mg) of the metal halide of indium and / or manganese is preferably 2 to 3% by mass and not more than 5% by mass relative to the enclosed mass (mg) of all metal halides. It is better to enclose in a range. Indium is more preferable.

  Further, at least one metal halide selected from the group consisting of calcium (Ca), cesium (Cs), lithium (Li), magnesium (Mg) and rubidium (Rb) is encapsulated in the metal halide. It is permissible to enclose the metal halide in a range of more than 0.05 and less than 0.4 with respect to the mass of the metal halide. By doing so, all the metals in the above group emit red light, which is effective in adjusting the color temperature of the high-pressure discharge lamp to be low.

  As the halogen constituting the metal halide in the discharge medium, it is preferable to mainly use iodine. If desired, an appropriate amount of bromine can be added, which suppresses blackening of the surrounding portion and improves the luminous flux maintenance factor.

  The starting gas contributes to starting discharge at least when starting the high-pressure discharge lamp. However, the specific gas type is not limited. In the case of a high-pressure discharge lamp for general illumination, argon (Ar) alone or a mixed gas of neon (Ne) and argon (Ar) can be preferably used. The sealing pressure of the starting gas is generally 8 to 80 kPa. If it is less than 8 kPa, starting becomes difficult as can be understood from the Paschen curve. Moreover, when it exceeds 80 kPa, a starting voltage will become high and will exceed the pressure | voltage resistance of a nozzle | cap | die.

  Mercury mainly contributes to lamp voltage formation as a buffer. However, as is well known, part of the characteristic spectrum due to mercury vapor also contributes to light emission. In addition, it is suitable to set the mercury enclosure amount per unit volume in the enclosure part of a translucent ceramic airtight container to 3-30 mg / cc.

  In order for metal thulium to function effectively as a halogen getter, the molar ratio A / B of the number of moles A (mol) of metal thulium to the number of moles B (mol) of all the metal halides enclosed is 0.03 to 0.03. It is better to set within the range of 0.16. Next, the reason will be described with reference to FIG.

  FIG. 2 is a graph showing the relationship between the molar ratio of metal thulium to all the enclosed metal halides, the extinction voltage, and the total luminous flux. In the figure, the horizontal axis represents metal thulium / metal halide (mol ratio), and the vertical axis represents the extinction voltage and the relative value (%) of the total luminous flux. Further, the curve with the measured value ♦ disappears and indicates the relative value (%) of the voltage characteristic, and the curve with the measured value □ indicates the relative value (%) of the total luminous flux of the lamp.

  As can be understood from the figure, the extinction voltage becomes too high when the metal thulium / metal halide (mol ratio) is less than 0.03 and exceeds the allowable range, but becomes low when 0.03 or more. On the other hand, the total luminous flux becomes too small when the metal thulium / metal halide (mol ratio) exceeds 0.16 and exceeds the allowable range, but increases when the metal thulium / metal halide (mol ratio) exceeds 0.16.

  In summary, if the metal thulium / metal halide (mol ratio) is within the range of 0.03 to 0.16 (mol%), the extinction voltage of the high-pressure discharge lamp is low and the total luminous flux is large. . Moreover, if it is the range of 0.04-0.12, it is still more effective.

  The aspect of enclosure of metal thulium in the translucent ceramic discharge vessel is not particularly limited in the present invention. Metal thulium can be sealed together with the discharge medium or alone, but if desired, the metal thulium can be sealed in the translucent ceramic hermetic container when sealed in the translucent ceramic hermetic container. Can be introduced. In addition, as an aspect of adhesion to the electrode, it is possible to employ winding of a metal thulium wire around the electrode tip or welding a metal thulium piece in the vicinity of the electrode tip.

  Thus, in the present invention, as shown in FIG. 3, since metal thulium acts as a halogen getter by encapsulating metal thulium, the extinction voltage is relatively lower than that of the comparative example in which metal thulium is not encapsulated. To do. FIG. 3 is a graph conceptually showing the relationship between the lamp voltage and the extinction voltage in a comparative example having the same configuration as that of the present invention except that metal thulium is sealed and thulium is not sealed. In the figure, the solid line indicates the present invention, and the dotted line indicates the comparative example.

  [Other Configurations] The present invention allows the following components to be included as other configurations.

  1. (Regarding the outer tube) The outer tube is a means for storing a light-emitting tube having a translucent ceramic hermetic container, a pair of electrodes, and an enclosure enclosed inside the translucent ceramic hermetic container in a predetermined position inside the outer tube. It is. Then, the arc tube is mechanically protected, the operation temperature of the arc tube is maintained within a desired range, or a function such as blocking a predetermined one of the emission from the arc tube is selectively performed on the outer tube or It can be given comprehensively.

  The outer tube and the arc tube are generally arranged so that their axes coincide. In order to perform a desired function, the outer tube can be filled with a vacuum or low-pressure atmosphere or an inert gas such as a rare gas or nitrogen. It is preferable to set the atmosphere in the outer tube to an inert gas such as nitrogen or air whose pressure is reduced to 133 Pa or less because this is effective in making the temperature distribution of the arc tube uniform. Note that the outer tube can be formed using a material having appropriate translucency, airtightness, heat resistance and workability, for example, hard glass. Also, various known shapes can be selectively employed as appropriate for the outer tube.

  In addition, the outer tube can selectively adopt either a single-sealed structure or a double-sided sealed structure as desired. Note that “single sealing” refers to a structure in which a pinch seal portion is formed only at one end of the outer tube, and the other end is closed without forming a sealing portion. On the other hand, “both ends sealing” refers to a structure in which pinch seal portions are formed at both ends of the outer tube. In addition, it is convenient for the general illumination which uses a general purpose lamp socket that an outer tube | pipe is a one-side sealing structure.

  2. (Regarding the Starter) A starter such as a high voltage pulse generator can be arranged in the outer tube to constitute a high-pressure discharge lamp adapted for a ballast for a mercury lamp. A conventional ceramic metal halide lamp with a built-in starter that is turned on by a general-purpose mercury lamp (copper iron type) ballast with a secondary voltage of 200 V has a problem that it is likely to turn off. According to the present invention, the turn-off voltage is reduced. Since it becomes low, it is particularly suitable for the high-pressure discharge lamp having a built-in starter. In addition, the high pressure discharge lamp having an average color rendering index Ra of 78 or more can be obtained.

  Further, when the starter is mainly composed of a glow starter that emits ultraviolet rays during operation, initial electrons are easily excited in the arc tube by the emitted ultraviolet rays, so that the starting is further facilitated.

3. Tube wall load of arc tube In the present invention, it is preferable to set the tube wall load of the arc tube in a range of ²⁰ to 35 W / cm ² . The tube wall load is a value obtained by dividing the lamp power by the area of the tube wall portion corresponding to between the electrodes.

    According to the present invention, in addition to the metal halides of thulium (Tm), sodium (Na) and thallium (Tl), metal thulium has a mole number A relative to the mole number B of all metal halides. Even if thulium ions generated from thulium halide and contributing to light emission disappear by sealing so that the ratio A / B is within the range of 0.03 to 0.16, the enclosed metal thulium is Capturing free halogen to form thulium halide to compensate for the disappearance of thulium ions, showing high luminous efficiency with thulium from the beginning of lighting, and maintaining this over a long period of time, and lowering the extinction voltage A high-pressure discharge lamp and a lighting fixture using the same can be provided. In particular, metal thulium has the highest getter action and luminous efficiency among various known halogen getters when encapsulating metal halides of thulium (Tm), sodium (Na) and thallium (Tl) as main components. The present invention proved to be preferable. Thulium halide has a relatively large amount of the above metal halides, so that it has an advantage that it does not easily affect lamp characteristics with respect to errors in the amount of metal thulium enclosed and variations in lighting temperature.

  Moreover, since the extinction voltage is reduced by enclosing metal thulium, it is particularly suitable for a high-pressure discharge lamp with a built-in starter and a lighting fixture using the same.

  In addition, if the mole% ratio of thulium halide to all metal halides is 20 to 30, a high-pressure discharge lamp having a very low extinction rate during lighting and high lamp efficiency and illumination using the same An instrument can be provided.

  Hereinafter, an embodiment for carrying out a metal vapor discharge lamp of the present invention will be described with reference to the drawings.

    4 and 5 show an embodiment for implementing the metal vapor discharge lamp of the present invention, FIG. 4 is a front view of the entire high-pressure discharge lamp, and FIG. 5 is a sectional view of the arc tube.

  In this embodiment, the metal vapor discharge lamp HPL is mainly configured to include an arc tube IT, an outer tube OT, a support structure SF, a starter ST, a shroud SH, and a base B as shown in FIG.

  First, the arc tube IT will be described. As shown in FIG. 5, the arc tube IT includes a translucent ceramic hermetic container 1, electrodes 2, 2, a pair of current introduction conductors 3, 3, a pair of seal portions 4, 4 and a translucent ceramic hermetic container 1. The enclosure is enclosed.

  The translucent ceramic hermetic container 1 is made of translucent polycrystalline alumina ceramics, and includes a surrounding portion 1a and a pair of small-diameter cylindrical portions 1b and 1b disposed in communication with both ends of the surrounding portion 1a. And the small diameter cylinder part 1b and the surrounding part 1a are integrally shape | molded by casting.

  The outer shape of the surrounding portion 1a bulges in a jade shape, and a discharge space having a substantially similar shape is formed therein.

  The pair of small-diameter cylindrical portions 1b and 1b integrally extend outward from both ends in the tube axis direction of the surrounding portion 1a along the tube axis direction.

  Each of the pair of electrodes 2 and 2 includes an electrode shaft 2a and an electrode main portion 2b. The electrode shaft 2a is inserted into the small diameter cylindrical portions 1b and 1b. The electrode main portion 2b is formed by winding a tungsten wire around the inner end of the electrode shaft portion 1a for several turns at a dense pitch. A slight gap called a capillary is formed between the elongated shaft portion 21 and the inner surfaces of the small diameter cylindrical portions 1b and 1b. The distance between the tips exposed in the surrounding portion 1a of the pair of electrodes 2 and 2 forms an interelectrode distance.

  In the present invention, the aspect ratio, which is the ratio of the interelectrode distance to the inner diameter of the surrounding portion 1a, is preferably in the range of 0.8 to 1.5. If the aspect ratio is less than 0.8, the coldest part temperature is too high, resulting in a short life, which is not suitable as a high-pressure discharge lamp for general illumination. On the other hand, if the aspect ratio exceeds 1.5, the coldest part temperature is too low, and it becomes difficult to obtain the desired coldest part temperature, and the average color rendering index Ra is unsuitable.

  The pair of current introduction conductors 3 and 3 are each composed of a niobium rod 3a and a molybdenum rod 3b. The niobium rod-shaped body 3a has a distal end inserted into the small diameter cylindrical portion 1b and a proximal end protruding from the small diameter cylindrical portion 1b to the outside. Molybdenum rod-shaped body 3b is butt welded to the tip of niobium rod-shaped body 3a, Mo fine wire is wound around the outer circumference of the Mo rod, and the base end of electrode shaft portion 2a is butt welded to the tip. 2 is supported.

The pair of seal portions 4, 4 is formed by heating and melting and solidifying a ceramic sealing compound made of, for example, Dy ₂ O ₃ —SiO ₂ —Al ₂ O ₃ . Thus, the pair of seal portions 4, 4 are interposed between the end surface side portions of the small-diameter cylindrical portions 1 b, 1 b of the translucent ceramic hermetic container 1 and the current introduction conductors 3, 3 facing the portions. Thus, the translucent ceramic hermetic container 1 is hermetically sealed to provide a so-called current introduction conductor insertion sealing structure, and the niobium rod-like body 3a of the current introduction conductors 3 and 3 is provided with the translucent ceramic hermetic container 1. The entire portion inserted into the small-diameter cylindrical portions 1b and 1b is covered so as not to be exposed inside. With the above sealing, the electrode 2 is fixed at a predetermined position of the translucent ceramic hermetic container 1.

  The enclosure includes a starting gas, for example, argon (Ar), a metal halide described below, and a discharge medium made of mercury for supplying buffer vapor, and metal thulium as a halogen getter, and a translucent ceramic hermetic container. 1 is enclosed. Since metal halide and mercury are encapsulated in excess of the amount that evaporates, some of them stay in a liquid phase state in a slight gap formed in the small diameter cylindrical portions 1b and 1b during stable lighting. ing. And the coldest part is formed in the surface layer part vicinity of the discharge medium which stays in the liquid phase state, for example in the small diameter cylinder part 1b used as the lower side during lighting.

  The metal halide includes at least thulium (Tm), sodium (Na), and thallium (Tl) metal halides. Further, if desired, a metal halide of cerium (Ce) or praseodymium (Pr), a halogen of indium (In) or manganese, calcium (Ca), cesium (Cs), lithium (Li), magnesium (Mg) and rubidium An appropriate amount of at least one metal halide selected from the group (Rb) can be selectively encapsulated.

  The outer tube OT has a BT bulb shape made of hard glass, and a flare stem 11 is sealed to the neck portion. The flare stem 11 introduces a pair of lead wires 11a and 11b in an airtight manner. The outer tube OT accommodates and stores the arc tube IT at a predetermined position inside the outer tube OT by a support structure SF described later.

  The support structure SF is formed by bending a metal rod-like body into a substantially U shape, and a lower portion thereof is welded to an introduction line 11b sealed to the flare stem 11, and a top holder 12 made of a spring material is provided on the upper portion. Are welded. The top holder 12 can be locked to the inner surface of the head of the outer tube OT, and locks the upper part of the support structure SF to the outer tube OT. The arc tube IT is connected to the belt-like conductor 13 that bridges the upper side of the support structure SF by caulking the current introduction conductor 3 at the upper part in FIG. Further, in FIG. 1 of the arc tube IT, the lower current introduction conductor 3 is welded to the introduction line 11a through the strand wire 14 and the connection conductor 15 in series.

  As described above, the arc tube IT is connected between the introduction lines 11a and 11b.

  The shroud SH is composed of a translucent cylinder 16 and a reinforcing string 17. The translucent cylinder 16 is made of a heat-resistant translucent member such as quartz glass, for example, has a cylindrical shape, and is disposed so as to surround the arc tube IT substantially concentrically from the side. Note that the shroud SH is open at both upper and lower ends in the figure, and an appropriate space is formed between the inner surface and the arc tube IT. The reinforcing string 17 is made of, for example, a heat-resistant inorganic fiber yarn mainly composed of alumina or the like and a stainless steel wire. The reinforcing string 17 is wound around the outer periphery of the translucent cylinder 16 so that the translucent cylinder 16 is formed from the outside. It is tightened and reinforced.

  The shroud SH is held by the support structure SF with its upper and lower ends sandwiched between a pair of shroud holders 18 and 18 disposed in the support structure SF. That is, the shroud holder 18 has a disc-shaped fitting portion fitted to the end portion of the translucent cylindrical body 16 of the shroud SH, and a mounting leg portion integral with the fitting portion is welded to the support structure SF. Thus, it is supported at a predetermined position. The translucent small-diameter cylindrical portion 1b of the arc tube IT penetrates the shroud holder 18 and protrudes outward from the shroud SH.

  The starter ST is means for assisting the start of the high-pressure discharge lamp HPL. In this embodiment, for example, a start glow starter (lighting tube) 19 and a thermally responsive switch using a bimetal (not visible in FIG. 1). And one end of the series circuit connected to the support structure SF and the other end of the series circuit connected to the connection conductor 15. Therefore, the arc tube IT and the starter ST are connected in parallel to the introduction lines 11a and 11b.

  The glow starter (lighting tube) 19 operates to induce a pulse voltage in the ballast when the bimetal separates from the discharge electrode and applies it to the high pressure discharge lamp HPL to start the high pressure discharge lamp HPL. Prior to the occurrence of glow discharge, ultraviolet rays are emitted to the outside to excite initial electrons in the high-pressure discharge lamp HPL. The ballast is a (general type / low start-up type) mercury lamp ballast.

  That is, the glow starter 19 is formed with a sealing portion in which a lead wire is hermetically sealed at one end of a bulb made of, for example, ultraviolet transmissive quartz glass, and a discharge electrode made of bimetal connected to the lead wire in the bulb. Are opposed to each other at a predetermined interval, and argon (Ar) is sealed at a predetermined pressure.

  Thus, the glow starter 19 causes glow discharge to occur between the bimetal disposed in the bulb and the discharge electrode when energized, and the argon gas emits ultraviolet rays. Since the emitted ultraviolet rays irradiate the inside of the arc tube IT and excite initial electrons in the arc tube IT, the high-pressure discharge lamp HPL can be easily started.

  The current limiting resistor 20 limits the glow current to a predetermined value. Since the high-pressure discharge lamp HPL is displaced due to a temperature rise when the high pressure discharge lamp HPL is started and lit, the thermal response switch is turned off, so that the operation of the starter ST is stopped during lighting.

  The base B is an E39 type base, and is fixed to the neck portion of the outer tube OT, and one of a pair of lead wires (not shown) exposed to the outside from the outer tube OT is connected to the shell portion and the other is connected to the center contact. ing.

  In FIG. 1, reference numeral G1 is a performance getter, and G2 is an initial getter, which cleans the inside of the outer tube OT and is welded to the upper part of the support structure SF.

  Next, examples will be described with reference to Comparative Example 1.

It is a high pressure discharge lamp of the form shown in FIG.
Inclusion material: NaI (50) -TlI (15) -TmI ₃ (25) -InI (10) = 5.0 mg, and parentheses indicate mol%.

Metal thulium (Tm) = 0.2mg
(Metal thulium (mol) / metal halide (mol) = 0.07)
Mercury and argon tube wall load: 22 W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 190W

[Comparative Example 1]
Discharge medium: NaI (50) -TlI (15) -TmI ₃ (25) -InI (10) = 5.0 mg, and the parentheses indicate mol%.

Metal thulium (Tm) = 0.6mg
(Metal thulium (mol) / metal halide (mol) = 0.20)
Mercury, argon tube wall load: 22W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 190W

[Comparative Example 2]
Discharge medium: NaI (50) -TlI (15) -TmI ₃ (25) -InI (10) = 5.0 mg, and the parentheses indicate mol%.

Metal thulium (Tm) = none (metal thulium (mol) / metal halide (mol) = 0)
Mercury and argon tube wall load: 22 W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 190W

The relationship between the metal thulium / metal halide molar ratio, the extinction voltage, and the total luminous flux in Example 1, Comparative Example 1, and Comparative Example 2 was the result along the graph shown in FIG. That is, the extinction voltage decreases in the order of Comparative Example 2, Example 1, and Comparative Example 1. In addition, the value of Example 1 and Comparative Example 1 exhibits a sufficient effect as a halogen getter.

  On the other hand, the total luminous flux is similarly decreased in the order of Comparative Example 2, Example 1, and Comparative Example 1. In addition, Example 1 is substantially the same value as Comparative Example 2 and there is no reduction in the total luminous flux, but Comparative Example 1 is greatly reduced.

Therefore, Example 1 shows that the present invention effectively reduces the extinction voltage while maintaining the value of the total luminous flux.

Discharge medium: NaI (50) -TlI (15) -TmI ₃ (25) -InI (10) = 10 mg, and the parentheses indicate mol%.

Metal thulium (Tm) = 0.4mg
(Metal thulium (mol) / metal halide (mol) = 0.07)
Mercury and argon tube wall load: 20 W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 280W

[Comparative Example 3]
Discharge medium: NaI (60) -TlI (18) -TmI ₃ (10) -InI (12) = 10 mg, and the parentheses indicate mol%.

Metal thulium (Tm) = 0.4mg
(Metal thulium (mol) / metal halide (mol) = 0.06)
Mercury and argon tube wall load: 20 W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 280W

[Comparative Example 4]
Discharge medium: NaI (40) -TlI (12) -TmI ₃ (40) -InI (8) = 12 mg, and the parentheses indicate mol%.

Metal thulium (Tm) = 0.4mg
(Metal thulium (mol) / metal halide (mol) = 0.08)
Mercury and argon tube wall load: 20 W / cm ²
Outer tube atmosphere: Vacuum rated lamp power: 280W

In Example 2, Comparative Example 3 and Comparative Example 4, the relationship between the molar percentage of thulium halide / metal halide, the occurrence rate of extinction during the lifetime, and the initial lamp efficiency is the result according to the graph shown in FIG. there were. That is, with regard to the occurrence rate of extinction during the lifetime, Comparative Example 3 and Example 2 were zero, but when the molar percentage of thulium halide / metal halide of Example 2 was exceeded, the incidence rate gradually increased, In Comparative Example 4, about 50% was generated.

  The initial lamp efficiency is higher in the order of Comparative Example 3, Example 2, and Comparative Example 4. However, the values were almost the same in the range of Example 2 or higher.

  Therefore, Example 2 shows that the present invention can realize a highly efficient lamp while suppressing the extinction during the lifetime.

    FIG. 6 is a front view of a lighting device for high ceiling as one embodiment for implementing the lighting device of the present invention. In the present invention, the luminaire is composed of the luminaire main body 20, the high-pressure discharge lamp HPL and the lighting device, and is a concept including various indoor and outdoor luminaires. Further, the lighting fixture may be for general lighting or special lighting. Note that the special illumination includes various uses other than the general illumination.

  In the figure, the luminaire main body 20 is composed of a remaining portion excluding the high-pressure discharge lamp HPL and the lighting device from the luminaire. In this embodiment, the luminaire main body 20 is configured with an attachment base 21, a support frame 22, a socket 23, and a reflector 24 as main components.

  The high-pressure discharge lamp HDL is the high-pressure discharge lamp of the present invention shown in FIGS.

  The lighting device is disposed separately from the luminaire main body 20, for example, on the ceiling. The circuit means for lighting the high-pressure discharge lamp HDL may be any of electronic means and those mainly composed of a core and a winding.

Graph showing the relationship between the extinction rate during the lifetime and the lamp efficiency with respect to the molar ratio of thulium halide / metal halide Graph showing the relationship between the molar ratio of metal thulium to all enclosed metal halides, extinction voltage, and total luminous flux Graph conceptually showing the relationship between lamp voltage and extinction voltage with and without metal thulium The partially cutaway front view of the whole high pressure discharge lamp in one form for carrying out the metal vapor discharge lamp of the present invention Similarly, cross-sectional view of arc tube Schematic diagram of a downlight as one form for implementing the luminaire of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Translucent ceramic airtight container, 1a ... Enveloping part, 1b ... Small diameter cylinder part, 2 ... Electrode, 3 ... Current introduction conductor, 4 ... Seal part, 11 ... Stem, B ... Base, G1 ... Performance getter, G2 ... initial getter, IT ... arc tube, OT ... outer tube, SF ... support structure, ST ... starter

Claims (5)

A translucent ceramic hermetic container;
A pair of electrodes sealed inside a translucent ceramic hermetic container;
It consists of a starting gas sealed in a light-transmitting ceramic hermetic vessel, a metal halide containing at least thulium (Tm), sodium (Na) and thallium (Tl), mercury, and metal thulium. mol), and when the number of moles of all metal halides is B (mol), the inclusion in which the molar ratio A / B satisfies the formula: 0.03 ≦ A / B ≦ 0.16;
A high-pressure discharge lamp comprising:   2. A high pressure discharge lamp according to claim 1, wherein the molar ratio of thulium halide to all metal halides is 20-30. An outer tube that houses a translucent ceramic hermetic container and whose inside is kept in vacuum;
A starting circuit disposed inside the outer tube;
The high pressure discharge lamp according to claim 1 or 2, further comprising:   4. The high-pressure discharge lamp according to claim 3, wherein the starting circuit is mainly composed of a glow starter that emits ultraviolet rays during operation. A lighting fixture body;
A high-pressure discharge lamp according to any one of claims 1 to 4 mounted on a luminaire body;
A lighting device for lighting the high-pressure discharge lamp;
The lighting fixture characterized by comprising.

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